In the UK, 16 year olds may choose not to continue their education, and of course, it was considered ideal to leave education at this age. I did A'levels until I was 18, then found full time work.
That is the problem in the UK, they get all this "don't go into higher education" and miss the point that in the USA most are in school until 18 so going on to do your 'A' levels after 16 shouldnt be a problem because then you'd be leaving the same time as those in the USA.
Used to really annoy me, being told not to carry on to 6th form and do 'A' levels because that was higher education.
i doubt I'd have done much work at university - i never used to study much in school and didn't revise for any of my gcse's except for my french written to memorise the verbs the morning before the exam.
instead i worked full time at 16 and went to college (paid by employer), I got my degree equivalent at 25.